WATERLOO - Summer has officially arrived.

Today's 94-degree high looks to beat Monday's sweltering temperatures and will be the hottest in about two years, said KWWL-TV meteorologist Mark Schnackenberg.

A high of 95 was recorded July 8, 2007. The warmest day last summer was 93 degrees July 7.

"Last year we didn't have very many 90-degree days," Schnackenberg said. "This year we may have three, four, maybe five days that we're at 90 degrees just this week."

The weather is part of a large area of high pressure across the middle of the country, Schnackenberg said. Much of the country is dealing with heat and humidity.

"The humidity level is as high as it ever really gets (today)," Schnackenberg said.

The National Weather Service in Des Moines has issued a heat advisory from noon to 7 p.m. today for much of Iowa, including Waterloo.

With humidity mixed it, it will feel like it is 100 degrees today, said meteorologist Miles Schumacher, with the weather service.

While the hot days may be uncomfortable, clear skies and dry weather are what Sturgis Falls organizers are hoping for this weekend. The annual Cedar Falls festival was scaled back last year because of massive flooding at Tourist, Island and Sturgis parks.

"They got all the fencing and everything in," said Jay Stoddard, Sturgis Falls president. "Basically all the work in the parks with trucks and everything, the set-up people got all that done."

The carnival moves in today and Wednesday, and will be ready to go Thursday.

"I was afraid to look ahead into Friday, Saturday and Sunday," Stoddard said. "I know this week (precipitation) looked minimal, but with all the heat and energy in the air, you can get a thunderstorm and lightning so quick. You can have everything perfect, but if the weather's not on your side, it definitely disrupts things."

The Falls Aquatic Center in Cedar Falls opened at noon Monday. About 45 minutes later, nearly 1,200 people had passed through the gate, said manager Evan Shanley.

"I bet we've doubled by now," Shanley said just after 2 p.m. Monday. "I believe we had a line out the door probably the first hour."

At 3 p.m., Jake Dolan with Mike Dolan Concrete and Masonry was taking a water break under the shady, covered walkway of the Fourth Street bridge. His crew was making repairs and working on the bike trail in the 100 block of Fourth Street.

"It sucks," said Dolan, wiping away sweat with a T-shirt. "I've just been running my head underneath the water faucet for a little bit. It wouldn't be so bad if it was cloudy. We just started getting a breeze here a little bit ago, but still."

Schnackenberg forecasted 90 degrees for the 7:05 p.m. first pitch at the Waterloo Bucks baseball game Monday night. A crowd of 1,192 braved sticky conditions for the ballpark-themed summertime St. Patty's Day.

Players would be stocked with water, said Bucks assistant general manager Aaron Rustad.

"It's going to be a scorcher out there," he said.

Don't expect relief from the heat until sometime Sunday, Schnackenberg said.

Wednesday should be a bit cooler with temperatures in the upper 80s, Schumacher said. Afternoon thunderstorms are likely, with rain possible into Thursday morning.

The latter part of the week will cool off. Overnight lows will fall into the 60s, instead of lower 70s. By next weekend, highs will be back to mid- to upper 80s.

"Since this is the first real long bout that we've had with hot weather this year, probably people need to kind of take it easy because you're not really all that acclimated to it," Schumacher said. "It can cause more problems when you're not ready for it."